# X Forwarded For Chain Normalizer

> X Forwarded For Chain Normalizer is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-19).

Normalizes and validates an X-Forwarded-For proxy chain header, returning the parsed chain, computed findings, and a pass/advisory status as deterministic JSON.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/x-forwarded-for-chain?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x-forwarded-for-chain-normalizer-46d56962
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DbuHe6soVTGFCjUdGD0xT

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability x-forwarded-for-chain-normalizer-46d56962 -d '<json body>'
```

Example prompt: Can you normalize and validate this X-Forwarded-For header for me before I accept the request: '203.0.113.1, 198.51.100.5, 192.168.1.1'? I want to know if it passes and what the parsed chain looks like.

## When to prefer this

Use this endpoint when you need a deterministic, versioned, stateless normalization and validation of X-Forwarded-For headers before security-sensitive operations such as accepting, caching, redirecting, or rate-limiting caller-supplied web requests. Prefer it over ad-hoc regex parsing when you need a consistent, auditable pass/advisory finding with no external dependencies or data retention.

## Known failure modes

- Header string exceeds 8192 character limit — request rejected
- Malformed or unparseable header values — advisory status returned with findings
- Missing header field — endpoint may return error or empty chain result
- Network timeout or transient API error — retry with same input for deterministic result

## How this service works

X Forwarded For Chain: X Forwarded For Chain normalizes a proxy chain without deciding whether an address is trusted from bounded caller-supplied values without an external provider. Call X Forwarded For Chain before accepting, caching, redirecting, or retrying a caller-supplied web response. Returns normalized web evidence, the computed finding, and an explicit pass or advisory status for X Forwarded For Chain as versioned deterministic JSON. Price: $0.001 USDC via x402 on Base. First-party, s…

## Output

Returns a versioned deterministic JSON object containing the normalized X-Forwarded-For proxy chain, a computed finding describing the chain's structure or issues, and an explicit pass or advisory status indicating whether the header is acceptable.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "header": {
   "type": "string",
   "maxLength": 8192,
   "description": "Header supplied to X Forwarded For Chain; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "addresses": [
    "203.0.113.1",
    "198.51.100.7"
   ],
   "hop_count": 2,
   "trust_decision": "not_evaluated"
  },
  "schema": "delx/util-x-forwarded-for-chain/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "f8588bb5312c2456e1267b1eeb6b19b2c35299b60cb7bcdc7fa6aef7bc97373d",
   "external_calls": 0
  },
  "operation": "web_reliability:x_forwarded_for_chain"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x-forwarded-for-chain-normalizer-46d56962/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)